Wireless communication network improved robustness for control of industrial equipment in harsh environments

ABSTRACT

In certain embodiments, a system includes a master node device. The master node device includes communication circuitry configured to facilitate communication with a welding power supply unit via a long-range communication link, and to facilitate wireless communication with one or more welding-related devices via a short-range wireless communication network. The master node device also includes control circuitry configured to continuously improve reliability of wireless communications between the communication circuitry and the one or more welding-related devices via the short-range wireless communication network.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Non provisional U.S. Patent Application of U.S.Provisional Patent Application No. 61/684,525, entitled “WirelessCommunication Network Improved Robustness for Control of IndustrialEquipment in Harsh Environments”, filed Aug. 17, 2012, which isincorporated herein by reference in its entirety.

BACKGROUND

The invention relates generally to communications between industrialequipment and, more specifically, to a wireless communication networkfor control of industrial equipment in harsh environments.

Welding-related devices, such as the welding wire feeders, weldingtorches, welding helmets, welding control pendants, welding foot pedals,and so forth, are often operated at welding locations that are remotefrom sources of power, such as welding power supply units. For example,such remote welding locations may be up to, or even greater than, 300feet from a source of power. As such, long cables are often extended tosuch remote welding locations, which can become very cumbersome.Moreover, in certain welding applications, such as ship buildingapplications, a number of remote welding locations may be used at anygiven time in relatively small areas, thereby exacerbating the problemof extending cables to these remote welding locations. Furthermore, theuse of wireless communication technologies in such environments hasheretofore proven problematic, at least due to noise considerations(which generally hamper wireless communication), securityconsiderations, and so forth.

BRIEF DESCRIPTION

These and other features, aspects, and advantages of the presentinvention will become better understood when the following detaileddescription is read with reference to the accompanying drawings in whichlike characters represent like parts throughout the drawings, wherein:

In one embodiment, a system includes a master node device. The masternode device includes communication circuitry configured to facilitatecommunication with a welding power supply unit via a long-rangecommunication link, and to facilitate wireless communication with one ormore welding-related devices via a short-range wireless communicationnetwork. The master node device also includes control circuitryconfigured to continuously improve reliability of wirelesscommunications between the communication circuitry and the one or morewelding-related devices via the short-range wireless communicationnetwork.

In another embodiment, a method includes wirelessly communicatingbetween one or more welding-related devices and a master node device viaa short-range wireless communication network. The method also includescommunicating between the master node device and a welding power supplyunit via a long-range communication link. The method further includescontinuously improving reliability of the short-range wirelesscommunication network.

In another embodiment, a wireless communication network includes one ormore welding-related devices. The one or more welding-related devicesinclude a welding wire feeder, a welding torch, a welding helmet, awelding pendant, or a welding foot pedal. The wireless communicationnetwork also includes a welding power supply unit configured to convertpower from a power grid to power for a welding operation performed usingthe one or more welding-related devices. The wireless communicationnetwork further includes a master node device configured to facilitatewireless communication between the one or more welding-related devicesand the master node device via a short-range wireless communicationnetwork, to facilitate communication between the master node device andthe welding power supply unit via a long-range communication link, andto continuously improve reliability of wireless communications betweenthe master node device and the one or more welding-related devices viathe short-range wireless communication network.

DRAWINGS

These and other features, aspects, and advantages of the presentinvention will become better understood when the following detaileddescription is read with reference to the accompanying drawings in whichlike characters represent like parts throughout the drawings, wherein:

FIG. 1 is a diagram of an embodiment of a welding system that mayutilize wireless communication networking techniques, in accordance withembodiments of the present disclosure;

FIG. 2 is a schematic diagram of an embodiment of the welding system ofFIG. 1 wherein many of the welding equipment and accessories of thewelding system form a local wireless network that communicates with theassociated welding power supply unit, which may be located remotely fromthe welding equipment and accessories of the welding system, inaccordance with embodiments of the present disclosure;

FIG. 3 is a schematic diagram of an embodiment of a welding applicationhaving a plurality of welding systems in operation at the same time,each welding system having their own local wireless networks andassociated welding supply units, in accordance with embodiments of thepresent disclosure;

FIG. 4 is a schematic diagram of an exemplary communication system of awelding system that implements external communication device connectionson a back end of the welding power supply unit, in accordance withembodiments of the present disclosure;

FIG. 5 is a schematic diagram of an exemplary communication system of awelding system that implements external communication device connectionson a front end of the welding power supply unit, in accordance withembodiments of the present disclosure;

FIG. 6 is a schematic diagram of an exemplary local wireless networkthat is attached to a range extending wireless router, in accordancewith the present disclosure;

FIG. 7 is a schematic diagram of a master node device and a weldingpower supply unit being associated with each other through simultaneousdepression of respective association buttons on the master node deviceand the welding power supply unit (or any other accessory node), inaccordance with embodiments of the present disclosure;

FIG. 8 is a schematic diagram of an exemplary welding power supply unit,master node device, and welding equipment/accessory node device,illustrating the internal circuitry of each device that facilitatesoperation of a local wireless network, in accordance with embodiments ofthe present disclosure; and

FIG. 9 is a schematic diagram illustrating the topology of a mesh-typenetwork of a plurality of master node devices and associated localwireless networks (e.g., weld cells) that communicate with each otherand share information about each other's capabilities, therebyfacilitating sensor data transmission from a plurality of sensors, inaccordance with embodiments of the present disclosure.

DETAILED DESCRIPTION

Turning to the figures, FIG. 1 is a diagram of an embodiment of awelding system 10 that may utilize wireless communication networkingtechniques, in accordance with embodiments of the present disclosure. Itshould be appreciated that, while the welding system 10 described hereinis specifically presented as a gas metal arc welding (GMAW) system 10,the presently disclosed wireless communication networking techniques mayalso be used with other arc welding processes (e.g., FCAW, FCAW-G, GTAW,SAW, SMAW, or similar arc welding processes). More specifically, asdescribed in greater detail below, all equipment and accessories used inthe welding system 10 may be configured to wirelessly communicate witheach other, as well as communicate with centralized or distributedwelding control systems. The welding system 10 includes a welding powersupply unit 12, a welding wire feeder 14, a gas supply system 16, and awelding torch 18. The welding power supply unit 12 generally suppliespower to the welding system 10 and other various accessories, and may becoupled to the welding wire feeder 14 via a weld cable 20 as well ascoupled to a workpiece 22 using a lead cable 24 having a clamp 26. Inthe illustrated embodiment, the welding wire feeder 14 is coupled to thewelding torch 18 via a weld cable 28 in order to supply welding wire andpower to the welding torch 18 during operation of the welding system 10.In another embodiment, the welding power supply unit 12 may couple anddirectly supply power to the welding torch 18.

In the embodiment illustrated in FIG. 1, the welding power supply unit12 may generally include power conversion circuitry that receives inputpower from an alternating current power source 30 (e.g., the AC powergrid, an engine/generator set, or a combination thereof), conditions theinput power, and provides DC or AC output power via the weld cable 20.As such, the welding power supply unit 12 may power the welding wirefeeder 14 that, in turn, powers the welding torch 18, in accordance withdemands of the welding system 10. The lead cable 24 terminating in theclamp 26 couples the welding power supply unit 12 to the workpiece 22 toclose the circuit between the welding power supply unit 12, theworkpiece 22, and the welding torch 18. The welding power supply unit 12may include circuit elements (e.g., transformers, rectifiers, switches,and so forth) capable of converting the AC input power to a directcurrent electrode positive (DCEP) output, direct current electrodenegative (DCEN) output, DC variable polarity, or a variable balance(e.g., balanced or unbalanced) AC output, as dictated by the demands ofthe welding system 10 (e.g., based on the type of welding processperformed by the welding system 10, and so forth).

The illustrated welding system 10 includes a gas supply system 16 thatsupplies a shielding gas or shielding gas mixtures to the welding torch18. In the depicted embodiment, the gas supply system 16 is directlycoupled to the welding torch 18 via a gas conduit 32 that is part of theweld cable 20 from the welding power supply unit 12. In anotherembodiment, the gas supply system 16 may instead be coupled to thewelding wire feeder 14, and the welding wire feeder 14 may regulate theflow of gas from the gas supply system 16 to the welding torch 18. Ashielding gas, as used herein, may refer to any gas or mixture of gasesthat may be provided to the arc and/or weld pool in order to provide aparticular local atmosphere (e.g., shield the arc, improve arcstability, limit the formation of metal oxides, improve wetting of themetal surfaces, alter the chemistry of the weld deposit, and so forth).

In addition, in certain embodiments, other welding equipment and weldingaccessories (e.g., welding-related devices) may be used in the weldingsystem 10. For example, in most welding applications, a welding helmet34 may be worn by an operator of the welding system 10. The weldinghelmet 34 provides protection to the operator of the welding system 10,particularly protecting the eyes of the operator from the flashingassociated with the welding arc during welding operations. In addition,in certain embodiments, the welding helmet 34 may provide feedback tothe operator related to parameters of the welding operations. Forexample, the welding helmet 34 may include an internal displayconfigured to display the welding parameters to the operator during thewelding operations. In addition, in certain embodiments, a weldingcontrol pendant 36 may be used to communicate between the welding wirefeeder 14 and the welding torch 18. The welding control pendant 36 is adevice that may be used at a welding application remote from anassociated welding power supply unit 12 and/or welding wire feeder 14,yet still provide substantially the same display and input devices thatthe remote welding power supply unit 12 and/or welding wire feeder 14provide. In other words, the welding control pendant 36 may be used as aremote control panel when it is not feasible or practical to use controlpanels on an associated remote welding power supply unit 12 and/orwelding wire feeder 14. In addition, in certain embodiments, a footpedal 38 may also be used in the welding system 10. The foot pedal 38may be used to adjust welding parameters of the welding power supplyunit 12 and/or the welding wire feeder 14. For example, when an operatorof the welding system 10 presses down on the foot pedal 38, a weldingwire feed speed and/or welding current from the welding wire feeder 14and/or the welding power supply unit 12 may be increased.

The welding equipment and accessories illustrated in FIG. 1 are merelyexemplary and not intended to be limiting. Many other types of weldingequipment and accessories may also be used in conjunction with thewelding system 10. As described in greater detail below, all weldingequipment and accessories used in association with the welding system 10may be configured to wirelessly communicate with each other, as well ascommunicate with centralized and/or distributed welding control systems.More specifically, the wireless communication networking techniquesdescribed herein include intelligent wireless nodes and electricalinterfaces to industrial equipment (e.g., in the exemplary weldingequipment and accessories illustrated in FIG. 1) to be used to controland coordinate command and data communications with and between otherindustrial equipment wirelessly, such that the communication networkenables seamless and secure exchange of welding parameters, as well asjob information and other user data, between the industrial equipment.Such wireless communication networking techniques enable weldingpersonnel or other industrial equipment personnel, with little or noexperience in areas of communication theory, radio frequency technology,or information technology, to easily assemble and operate wirelesscommunication networks that include a plurality of various equipment andaccessories, such as the welding equipment and accessories illustratedin FIG. 1. The wireless communication networking techniques describedherein make it easy and intuitive for the aforementioned personnel tomanually assemble a wireless network at the job site, and begin usingsuch wireless networks to perform safe and secure control of the weldingequipment and accessories, as well as exchange information with otherparties in the welding shop or at areas remote from the welding shop.

FIG. 2 is a schematic diagram of an embodiment of the welding system 10of FIG. 1 wherein many of the welding equipment and accessories (e.g.,the welding wire feeder 14, the welding torch 18, the welding helmet 34,the welding control pendant 36, the foot pedal 38, and so forth) of thewelding system 10 form a local wireless network 40 that communicateswith the associated welding power supply unit 12, which may be locatedremotely (e.g., up to or exceeding 300 feet away) from the weldingequipment and accessories of the welding system 10, in accordance withembodiments of the present disclosure. More specifically, each of thewelding equipment and accessories of the welding system 10 may bespecifically configured to communicate wirelessly with a master nodedevice 42 that, in turn, communicates with the respective welding powersupply unit 12 of the welding system 10. As such, the local wirelessnetwork 40 is formed as a star configuration between the master nodedevice 42 and the welding equipment and accessories of the weldingsystem 10 (e.g., via local wireless connections 44), and the localnetwork 40 communicates wirelessly with the respective welding powersupply unit 12 through the master node device 42 (e.g., via a long-rangecommunication connection 46), which functions as a network controllerfor the local wireless network 40. As described in greater detail below,in certain embodiments, the long-range communication connection 46 maybe a long-range wireless communication connection (e.g., using wirelesscommunication techniques), as illustrated in FIG. 2. However, in otherembodiments, the long-range communication connection 46 may be along-range wired communication connection (e.g., using wiredcommunication techniques). Indeed, in certain embodiments, the masternode device 42 may be configured to communicate with the welding powersupply unit 12 in both (or either, depending on operating conditions) awireless mode and a wired mode.

It will be appreciated that, in any particular industrial setting, morethan one welding system 10 may be used in relatively close proximity ofone another. For example, in a ship building application, severalwelding systems 10 having several associated welding power supply units12 may be used at any given time on the ship being constructed. In sucha scenario, multiple local wireless networks 40 may be established(e.g., one for each welding system 10). FIG. 3 is a schematic diagram ofan embodiment of a welding application 48 having a plurality of weldingsystems 10 in operation at the same time, each welding system 10 havingtheir own local wireless network 40 and associated welding power supplyunit 12. As illustrated in FIG. 3, some of the welding systems 10 mayhave their respective welding power supply units 12 located within thelocal wireless coverage zone (e.g., within approximately 20-25 feet, incertain embodiments) of the respective local wireless network 40,whereas many other welding systems 10 may have their respective weldingpower supply units 12 located outside of the local wireless coveragezone of the respective local wireless network 40. In addition, many ofthe local wireless coverage zones of the local wireless networks 40 mayoverlap. As described in greater detail below, the wirelesscommunication networking techniques presented herein address any issuesthat may arise with respect to such overlapping wireless coverage.

FIG. 4 is a schematic diagram of an exemplary communication system 50 ofa welding system 10 that implements external communication deviceconnections on a back end of the welding power supply unit 12, and FIG.5 is a schematic diagram of an exemplary communication system 50 of awelding system 10 that implements external communication deviceconnections on a front end of the welding power supply unit 12, inaccordance with embodiments of the present disclosure. The communicationsystem 50 described herein specifies a local wireless network 40configured as a specific star configuration, and formed by a networkcontroller (i.e., the master node device 42) and various weldingequipment/accessory node devices 52 (e.g., the welding wire feeder 14,the welding torch 18, the welding helmet 34, the welding control pendant36, the foot pedal 38, and so forth) located within a reasonably shortdistance of each other. For example, the reasonably short distance maybe approximately 20-25 feet from the master node device 42 and, incertain embodiments, may be in a range of approximately 10 feet toapproximately 50 feet from the master node device 42, in a range ofapproximately 15 feet to approximately 40 feet from the master nodedevice 42, in a range of approximately 20 feet to approximately 30 feetfrom the master node device 42, or any other suitable range. Thephysical size (e.g., wireless transmission range) of the local wirelessnetwork 40 is not necessarily fixed, nor is it an absolute requirementfor proper operation of the local wireless network 40. For example, incertain embodiments, the operating (e.g., wireless transmission) rangeof the local wireless network 40 may be a parameter of the master nodedevice 42, which may be automatically adjusted by the master node device42 to provide optimum wireless communication link quality. Although notbeing a fixed parameter or being an absolute requirement for operationof the local wireless network 40, the shorter the distance (e.g.,wireless operating range) of the local wireless network 40, the morelikely the wireless communication link integrity will remain relativelyhigh. For example, radio frequency (RF) waves that travel shorterdistances will generally maintain higher communication link integrity.Furthermore, shorter communication distances of the local wirelessnetwork 40 may even further enhance the security of the local wirelessnetwork 40, as well as ensure that other local wireless networks 40 donot potentially interfere with each other.

The communications traffic from each equipment/accessory node device 52is sent to the master node device 42, which acts as a router andprioritization controller, and which ultimately routes the correctmessages in the proper order to their final destinations, as illustratedin FIGS. 4 and 5. More specifically, in certain embodiments, the masternode device 42 communicates with the welding power supply unit 12 of thewelding system 10 via a radio frequency (RF) communication link as thelong-range communication connection 46. As such, the master node device42 may communicate with the welding power supply unit 12, which may belocated at distances of up to, or exceeding, 300 feet from the masternode device 42, without using wired communication. However, in certainembodiments, the weld cables 20, 28 (or dedicated digital linkconnections) may be used as backup communication channels in the eventthat conditions do not allow communication over the long-rangecommunication connection 46 between the master node device 42 and theassociated welding power supply unit 12.

In certain embodiments where the welding wire feeder 14 is usedproximate to the local wireless network 40 and remote from the weldingpower supply unit 12, the master node device 42 may be attached at theend of the weld cable 20 illustrated in FIG. 1 proximate to, forexample, the welding wire feeder 14. Similarly, in certain embodimentswhere the welding wire feeder 14 is used remotely from the localwireless network 40 (e.g., proximate to the welding power supply unit12), the master node device 42 may be attached at the end of the weldcable 28 illustrated in FIG. 1 (or a dedicated digital communicationcable) proximate to, for example, the welding torch 18. As describedabove, the master node device 42 is a wireless device that is associatedwith the local wireless network 40 and, through its physical placementproximate to the welding operations, enables a relatively long rangelink to the welding power supply unit 12 to be extended or made to coverareas normally blocked by physical obstructions like metal or denseconcrete walls, mounds of dirt, and so forth. The long-rangecommunication connection 46 (e.g., an RF communication link, in certainembodiments) is considered a special link with the local wirelessnetwork 40 due to the physical constraints placed on it, such as therelatively long signal travel distance, possible loss of RF line ofsight, excessive reflections caused by multi-path effects, relativelylow RF transmission power, and so forth.

The local wireless network 40 that is assembled by the user will besecure insofar as only equipment and accessories with the propercredentials and having synchronized “user intent” information areallowed to “associate” with the local wireless network 40. In addition,the master node device 42 is allowed to control only one welding powersupply unit 12. In certain embodiments, the final destinations forcontrol and communication data originated in the local wireless network40 are the various welding equipment/accessory node devices 52. Forexample, as illustrated in FIGS. 4 and 5, the welding power supply unit12 allows an operator working within the coverage area of the localwireless network 40 to control the welding power supply unit 12, as wellas to read operating parameters (e.g., voltage and amperage settings,contactor on/off status, and so forth) from the welding power supplyunit 12. In the embodiment illustrated in FIG. 4, the welding powersupply unit 12 may provide access for data from the local wirelessnetwork 40 to be transferred to remote locations on the Internet 54(e.g., to cloud storage, for example) through various hardwareinterfaces (e.g., a “back end” of the welding power supply unit 12) suchas, but not limited to, cellular network communications 56, WiFi access58, a wired Ethernet connection 60 (e.g., a local area network (LAN)), aglobal positioning system (GPS) 62, and so forth.

The local wireless network 40, through implementation of specialsecurity features described herein, connects to what is referred to asthe “front end” of the welding power supply unit 12 or other industrialequipment to be controlled, by the local wireless network 40. Access tothe front end allows full control over the power supply and lockout ofthe normal user interfaces (e.g., on the welding power supply unit 12)in order to ensure personnel safety. The control philosophy is thatthere may be only one human controller of the welding equipment andaccessories (e.g., the welding equipment/accessory node devices 52)associated with the welding power supply unit 12 at any one time. Thelocal wireless network 40 implements several security features toprevent unauthorized access to the local wireless network 40, andthereby to the front end of the device being controlled (e.g., thewelding power supply unit 12).

Data transfer from the front end of the welding power supply unit 12 tothe “back end” of the welding power supply unit 12 (through whichcommunications to/from the welding power supply unit 12 are made), andvice versa, may be controlled through a proprietary security firewall(e.g., within the welding power supply unit 12) that is designed tosatisfy all the requirements of equipment safety and authorized accessof the data generated in the local wireless network 40. In situationswhere the welding power supply unit 12 does not implement a back endconnection to external (public) networks (see, e.g., FIG. 5), a methodof providing a gateway on the front end (e.g., of the welding powersupply unit 12) allows access to the Internet 54 (e.g., to cloudstorage, or other centralized and/or distributed control system). Assuch, in the event that the welding power supply unit 12 does notpossess the hardware and/or software required to implement back endconnectivity to the Internet 54, a special gateway device may beimplemented that provides the connections. For example, this type ofconnectivity may be implemented in a dongle-type device 64, which mayimplement both the front end functionality and the back endfunctionality when connected to either or all of the cellular networkcommunications 56, the WiFi access 58, the wired Ethernet connection 60,the GPS 62, and so forth. Such dongle-type device 64 may plug into aneasily accessible connector on the welding power supply unit 12,allowing the dongle-type device 64 to draw the power necessary forfull-time maintenance of the various communication links.Advantageously, older welding power supply units 12 already in the fieldmay be retrofitted with such a dongle-type device 64, allowing them toprovide intelligent control of the welding power supply unit 12, inaddition to data access to the Internet 54. In other words, the wirelessnode connections from the welding power supply unit 12 may be eitherbuilt into the welding power supply unit 12 or supported as adongle-type device 64, which may be plugged into some access portconnector implemented in the welding power supply unit 12.

The master node device 42 is a device that maintains a relativelylong-range (e.g., up to, or even exceeding, 300 feet in length)communication connection 46 with the welding power supply unit 12 of thewelding system 10 such that the data integrity of the link between thetwo is relatively high, while providing fail safe modes of operation.The master node device 42 also controls the local wireless network 40formed by the various welding equipment/accessory node devices 52 thathave been successfully associated with the local wireless network 40,and maintains relatively high link quality of service (LQS) with thosewelding equipment/accessory node devices 52. The long-rangecommunication connection 46 between the master node device 42 and thewelding power supply unit 12 may be an RF link or hardwired digitalcommunication of a “differential signaling” mode such as, but notlimited to, RS-485, RS-422, RS-644 and others.

In certain embodiments, the master node device 42 may be physicallylocated within or adjacent to the enclosures of any of the weldingequipment/accessory node devices 52 illustrated in FIGS. 4 and 5. Inother words, in certain embodiments, the master node device 42 may beimplemented in the welding wire feeder 14, in the welding torch 18, inthe welding helmet 34, in the welding control pendant 36, in the footpedal 38, and so forth. For example, as described above, the weldingwire feeder 14 feeds welding wire of various types and sizes to thewelding torch 18 to accomplish the act of welding. Wire feederstypically take their input from welding power supplies, such as thewelding power supply unit 12, and produce welding wire feed speedsrelative to the energy being delivered through weld cables (e.g., theweld cables 20, 28 illustrated in FIG. 1) to a welding torch (e.g., thewelding torch 18). In certain embodiments, the functionality of themaster node device 42 may be implemented within an enclosure (e.g.,housing) of the welding wire feeder 14.

As another example, as described above, the welding helmet 34 is adevice that is worn on the head of an operator of the welding system 10,and which shields the eyes of the operator from ultraviolet (UV) raysand debris generated during the welding process. The welding helmet 34may also provide data to the operator (e.g., through the use of adisplay panel or other indicator lights within the welding helmet 34)relating to welding parameters currently set on the welding power supplyunit 12, such as voltage, current, contact closure status, and so forth.The welding helmet 34 may also send data to the welding power supplyunit 12, wherein the data is generated by the operator (e.g., throughactivation of buttons, keypads, and other user interface elements on thewelding helmet 34). In certain embodiments, the functionality of themaster node device 42 may be implemented within the welding helmet 34.

As a further example, as described above, the welding control pendant 36is often a battery-powered, hand-held device with a graphics display or7-segment display that provides a user interface, allowing the operatorto observe the welding parameters and settings of the welding powersupply unit 12 (and, in certain embodiments, the welding wire feeder14), as well as send commands to the welding power supply unit 12 (and,in certain embodiments, the welding wire feeder 14) to operate invarious modes. In certain embodiments, the welding control pendant 36has several control buttons that allow for operator control of thewelding power supply unit 12. In addition, other information from thevarious welding equipment/accessory node devices 52 of the localwireless network 40 may be displayed on the welding control pendant 36and/or sent from the welding control pendant 36 to other weldingequipment/accessory node devices 52 of the local wireless network 40. Incertain embodiments, the functionality of the master node device 42 maybe implemented within the welding control pendant 36.

As a further example, as described above, the foot pedal 38 is a devicelocated on the floor that allows the operator of the welding system 10to depress its top platform in order to signal to the welding powersupply unit 12 (and, in certain embodiments, the welding wire feeder 14)certain adjustments to the voltage, current, contactor state, and soforth. In certain embodiments, the functionality of the master nodedevice 42 may be implemented within the body of the foot pedal 38. Inaddition, in certain embodiments, the functionality of the master nodedevice 42 may be implemented within the body of the welding torch 18.

As illustrated in FIGS. 4 and 5, the local wireless network 40 may alsoinclude a plurality of sensors 66 that, in certain embodiments, may bebattery-powered RF devices that can communicate with any nearby masternode device 42. The sensors 66 may send data through the master nodedevice 42 such that the data may be uploaded to the Internet 54. Incertain embodiments, the sensors 66 may not actually even be associatedwith operations of the particular local wireless network 40. In otherwords, certain sensors 66 may not be used to control the welding powersupply unit 12 associated with the master node device 42 through whichthe sensors 66 communicate. However, the sensors 66 may nevertheless beallowed to use the local wireless network 40 and freely associate withany local wireless network 40 in order to allow for their data payloadto be transported to a specific destination (e.g., cloud storage orother centralized and/or distributed control system). In other words,the master node devices 42 may be used to enable data communication ofthe sensors 66 regardless of whether the sensors 66 are part of thewelding system 10 that is used for welding operations, and do notrequire any manual association means to join a local wireless network40.

In certain situations using a long-range wireless communicationconnection 46, the distances between the master node device 42 and thewelding power supply unit 12 being controlled may be longer than the RFwaves (or other wireless signals) of the master node device 42 maytravel with no (or acceptable) loss of integrity. As such, in theseinstances, a range extending wireless router 68 may be used to bridgethe gap between the master node device 42 and the associated weldingpower supply unit 12. FIG. 6 is a schematic diagram of an exemplarylocal wireless network 40 that is attached to a range extending wirelessrouter 68, in accordance with the present disclosure. As with the masternode devices 42, an ideal range of the range extending wireless routers68 may be approximately 300 feet, and if the distance between the masternode device 42 and the associated welding power supply unit 12 issubstantially greater than 300 feet, a range extending wireless router68 may be located between the master node device 42 and the associatedwelding power supply unit 12.

In certain embodiments, as described in greater detail below, theassociations between a master node device 42 and the various weldingequipment/accessory node devices 52 of the local wireless network 40 areformed when the operator of the welding system 10 holds two devices inclose proximity (e.g., within approximately two feet) and simultaneouslypresses “associate” buttons on each device. For example, FIG. 7 is aschematic diagram of a master node device 42 and a welding power supplyunit 12 being associated with each other through simultaneous depressionof respective association buttons 70 on the master node device 42 andthe welding power supply unit 12 (or any other accessory node), inaccordance with embodiments of the present disclosure. Althoughillustrated as being buttons 70, any suitable means (e.g.,synchronization mechanism) for manually initiating association of thedevices may be used in certain embodiments, so long as thesynchronization mechanism is adequately conveys the wishes of thewelding operator to join the devices into a control and command network(e.g., the local wireless network 40). The various weldingequipment/accessory node devices 52 also include similar means formanually initiating association of the welding equipment/accessory nodedevices 52 with the master node device 42. As such, the associationprocedure accepts user intent in forming the local wireless network 40,which once formed will be used for the duration of a networking sessionto control and monitor the welding power supply unit 12 associated withthe master node device 42. Once the local wireless network 40 isestablished, additional welding equipment/accessory node devices 52 maybe added to the local wireless network 40 by repeating the associationprocedure between the master node device 42 and the additional weldingequipment/accessory node devices 52.

The master node device 42 keeps track of and controls all aspects ofcommunication between the welding equipment/accessory node devices 52associated with the local wireless network 40 of the master node device42 until a control session has ended. Ending a control session may beaccomplished in several ways. For example, the control session may beended when the master node device 42 is removed from the local wirelessnetwork 40. As an example, if the master node device 42 has not receivedor transmitted a control signal to or from the local wireless network 40for a specified period of time (e.g., approximately 5 seconds in certainembodiments), the control session of the local wireless network 40 maybe ended. This condition may occur if the master node device 42 ispowered off, or if the master node device 42 is prevented through anymeans from communicating with its associated welding equipment/accessorynode devices 52. In certain embodiments, in the absence of valid“heartbeats” (i.e., communications either to or from the master nodedevice 42), each welding equipment/accessory node device 52 willdisassociate itself from the local wireless network 40, set itscorresponding function to idle, and enter a standby or sleep mode. Thisheartbeat mechanism may intelligently return the welding power supplyunit 12 to a safe condition if the communication link between the masternode device 42 and the welding power supply unit 12 is interrupted.Another situation where the control session may be ended is when thewelding power supply unit 12 “disappears” from the local wirelessnetwork 40 to which it was associated, such as when the interfacedongle-type device 64 has been removed from the access port connector ofthe welding power supply unit 12, or when the welding power supply unit12 has been removed from a power source (with the welding power supplyunit 12 not having access to an alternate source of backup power). Incertain embodiments, if the master node device 42 observes that thewelding power supply unit 12 is not accessible for a specified period oftime (e.g., approximately 5 seconds in certain embodiments), the masternode device 42 may determine that the control session of the localwireless network 40 has ended, disassociate the associated weldingequipment/accessory node devices 52 from the local wireless network 40,close the networking session, and put itself in a standby or sleep mode.

Once a local wireless network 40 is established, commands and messagesmay be sent to the welding power supply unit 12 from the master nodedevice 42, such messages originating either in the master node device 42or in the associated welding equipment/accessory node devices 52.Commands and messages received by the master node device 42 from theassociated welding equipment/accessory node devices 52 are packetized,combined in an optimum data size and packet rate, and either buffered orsent immediately by the master node device 42 to the welding powersupply unit 12. Each communication is acknowledged by the receiver, andchecked for integrity using checksums, AES (advanced encryptionstandard) security signatures, and so forth.

Therefore, the local wireless network 40 implements wirelesscommunication networking techniques for controlling and coordinatingcommand and data communications between various pieces of industrialequipment (e.g., the welding equipment/accessory node devices 52). Morespecifically, the local wireless network 40 includes intelligentwireless nodes with electrical interfaces to industrial equipment, suchas the welding equipment/accessory node devices 52 and the welding powersupply unit 12. The wireless communication techniques described hereinallow for reuse of the welding equipment/accessory node devices 52 byother personnel in other locations once a job is completed bydisassociating the old local wireless network 40 and manuallyreprogramming the welding equipment/accessory node devices 52 as thewelding equipment/accessory node devices 52 of the new local wirelessnetwork 40 through the simple and intuitive methods described herein.

In addition, the wireless communication networking techniques describedherein provide improved network robustness. For example, the wirelesscommunication networking techniques described herein allow multiplelocal wireless networks 40 to be operated within RF range of each otherwithout harm or disruption occurring in adjacent wireless networks(e.g., other local wireless networks 40). In particular, thearchitecture is robust and intelligent enough to handle a multitude ofwireless control and communication networks in a welding shop ofindustrial fabrication facility. For example, in certain embodiments,the master node device 42, upon establishing a new local wirelessnetwork 40, will scan all channels in the ISM (industrial scientific andmedical band) frequency range looking for other master node devices 42operating adjacent local wireless networks 40. If an adjacent masternode device 42 is found using the same ISM channel, the scanning masternode device 42 will investigate the possibility of moving its own localwireless network 40 to another channel, and will communicate thatinformation to the other master node devices 42 that have been detectedin the vicinity.

Furthermore, the wireless communication networking techniques describedherein provide improved methods of dealing with interference from otherwireless nodes operating in the unlicensed ISM band, such as WiFi,Bluetooth, or Zigbee radios, or general noise sources such as otherwelding power supply units 12 operating in the vicinity. Such weldingnoise has the potential of generating large RF energy spikes infrequency bands that overlap the ISM band. The master node device 42,upon establishing a new local wireless network 40, will scan allchannels in the ISM band looking for noise sources. If noise sources aredetected in the ISM channel currently used by the master node device 42,the master node device 42 will investigate other ISM channels to moveto, and when a suitable ISM channel has been found, the master nodedevice 42 will reprogram all of its associated weldingequipment/accessory node devices 52 to the new ISM channel number. Incertain embodiments, a recursive check may continuously try to find themost noise-free ISM channel available.

Moreover, the wireless communication networking techniques describedherein provide improved power optimization of the weldingequipment/accessory node devices 52. For example, the wirelesscommunication networking techniques described herein allows for lowpower operation and programmable wake times for weldingequipment/accessory node devices 52 assembled in the local wirelessnetwork 40. The timing parameters related to powering the weldingequipment/accessory node devices 52 are determined based on theoperator's need for bandwidth and responsiveness, balanced around afunction of available battery energy. Each master node device 42determines the requirements of the welding equipment/accessory nodedevices 52 associated with it, and performs power management on thewelding equipment/accessory node devices 52 requesting support. Weldingequipment/accessory node devices 52 that need to have their powermanaged by the master node device 42 may be put into sleep mode with awake timer programmed for a time period that still allows for theminimum response time required by the network parameters for propercommunication and acceptable response latency. If the latency requiredis 0 (or instantaneous), none of the welding equipment/accessory nodedevices 52 in the local wireless network 40 will be allowed to go intosleep mode.

Once programmed with a wake time, each welding equipment/accessory nodedevice 52 requesting power management may be put in a “deep sleep mode”for the predefined period of time. When the sleep period elapses, thewelding equipment/accessory node device 52 wakes up and is available torespond to a heartbeat acknowledgement message that is sent from themaster node device 42. When welding equipment/accessory node devices 52are disassociated from the local wireless network 40, they areprogrammed to go into the deep sleep mode, from which they will onlywake up when an operator attempts to associate them into a new localwireless network 40.

In certain embodiments, the wireless communication networking techniquesdescribed herein may additionally provide an “adaptive” method ofdetermining when to check for noise sources on different radio channelsbased on history and time averages accumulated as a result of continuedoperation at a given job site. Using adaptive techniques enables themaster node device 42 to maximize battery life of the weldingequipment/accessory node devices 52 by understanding and predicting whennoise mitigation countermeasures are more likely needed to be employed.

In addition, the wireless communication networking techniques describedherein provide improved association and security of weldingequipment/accessory node devices 52 within a given local wirelessnetwork 40. For example, the wireless communication networkingtechniques described herein enable workers in industrial settings, suchas welders in an industrial fabrication setting, to associate differentindustrial equipment devices (e.g., the welding equipment/accessory nodedevices 52 described herein) by simply bringing them in close proximityto each other and simultaneously pressing association buttons 70 on bothdevices, forming a secure control and communication network (e.g., thelocal wireless network 40). Additional devices (e.g., the weldingequipment/accessory node devices 52 described herein) may thus be addedto the local wireless network 40 by associating them with the masternode device 42.

Furthermore, the wireless communication networking techniques describedherein provide for network sensor information to be collected anddistributed as needed. For example, the wireless communicationnetworking techniques described herein allow sensor nodes (e.g., thesensors 66) in industrial settings to associate with any nearby localwireless networks 40, allowing transport of sensor data to a localsupervisor, to cloud storage, to centralized and/or distributed controlsystems, and so forth. The sensors 66 that have been programmed with anIP address of a final destination may request access to that locationfrom any nearby local wireless networks 40, and such local wirelessnetworks 40 will (through intelligent mapping of their capabilities andcapabilities of other nearby networks) allow the sensor data to beforwarded on to its final destination. In certain embodiments, thesensors 66 will not destroy their local data (e.g., if infinite dataretention has not been enabled) until they receive a secureacknowledgement from the final destination that the sensor data wasreceived and is not corrupted in any way.

FIG. 8 is a schematic diagram of an exemplary welding power supply unit12, master node device 42, and welding equipment/accessory node device52 (e.g., the welding wire feeder 14, the welding torch 18, the weldinghelmet 34, the welding control pendant 36, the foot pedal 38, and soforth), illustrating the internal circuitry of each device thatfacilitates operation of a local wireless network 40, in accordance withembodiments of the present disclosure. For example, as illustrated inFIG. 8, the master node device 42 includes wireless communicationcircuitry 72 configured to facilitate wireless communication with thewelding power supply unit 12 via a long-range wireless communicationlink (e.g., the long-range communication connection 46 illustrated inFIGS. 2-5), and to facilitate wireless communication with one or morewelding-related devices (e.g., the welding equipment/accessory nodedevices 52) via a short-range wireless communication network (e.g., thelocal wireless connections 44 of the local wireless network 40). As willbe appreciated, the welding power supply unit 12 also includes wirelesscommunication circuitry 72 configured to facilitate the wirelesscommunication with the master node device 42 via the long-range wirelesscommunication link (e.g., the long-range communication connection 46illustrated in FIGS. 2-5). In addition, the welding equipment/accessorynode devices 52 also include wireless communication circuitry 72configured to facilitate the wireless communication with the master nodedevice 42 via the short-range wireless communication network (e.g., thelocal wireless connections 44 of the local wireless network 40).

As described above, in certain embodiments, the long-range wirelesscommunication link (e.g., the long-range communication connection 46illustrated in FIGS. 2-5) between the welding power supply unit 12 andthe master node device 42 may be formed as an RF communication link, andthe short-range wireless communication network (e.g., the local wirelessconnections 44 of the local wireless network 40) between the weldingequipment/accessory node devices 52 and the master node device 42 maysimilarly utilize RF communication techniques. As such, in certainembodiments, the wireless communication circuitry 72 of the devices mayinclude RF communication circuitry, such as RF transmitters and sensors.However, in other embodiments, any suitable means for communicatingwirelessly between the welding power supply unit 12 and the master nodedevice 42 and between the welding equipment/accessory node devices 52and the master node device 42 may be utilized.

As described above, the wireless communication circuitry 72 of themaster node device 42 and the wireless communication circuitry 72 of thewelding power supply unit 12 may be configured to establish and utilizethe long-range wireless communication link (e.g., the long-rangecommunication connection 46 illustrated in FIGS. 2-5) between thewelding power supply unit 12 and the master node device 42 at atransmission range of approximately 300 feet. However, in otherembodiments, the transmission range of the long-range wirelesscommunication link (e.g., the long-range communication connection 46illustrated in FIGS. 2-5) between the welding power supply unit 12 andthe master node device 42 may exceed the 300 feet previously mentionedherein.

In addition, as described above, the wireless communication circuitry 72of the master node device 42 and the wireless communication circuitry 72of the welding equipment/accessory node devices 52 may be configured toestablish and utilize the short-range wireless communication network(e.g., the local wireless connections 44 of the local wireless network40) between the welding equipment/accessory node devices 52 and themaster node device 42 at a transmission range of approximately 20-25feet from the master node device 42. However, in other embodiments, thetransmission range of the short-range wireless communication network(e.g., the local wireless connections 44 of the local wireless network40) between the welding equipment/accessory node devices 52 and themaster node device 42 may be in a range of approximately 10 feet toapproximately 50 feet from the master node device 42, in a range ofapproximately 15 feet to approximately 40 feet from the master nodedevice 42, in a range of approximately 20 feet to approximately 30 feetfrom the master node device 42, or any other suitable range. In general,the local wireless connections 44 of the local wireless network 40 arecreated by lowering the power of the wireless communication circuitry 72such that they do not radiate too far, thereby wasting power andpotentially interfering with other nearby devices.

In addition, as illustrated in FIG. 8, in certain embodiments, themaster node device 42 and the welding power supply unit 12 include wiredcommunication circuitry 74 configured to facilitate wired digitalcommunication (e.g., welding cable communication (WCC), as well as otherforms of wired digital communication) with the welding power supply unit12 via a weld cable (e.g., the weld cables 20, 28) or other wireddigital communication link either as a primary mode of communication, orwhen communication over the long-range wireless communication link(e.g., the long-range communication connection 46 illustrated in FIGS.2-5) between the welding power supply unit 12 and the master node device42 is not allowed (e.g., during temporary interruption of the long-rangecommunication connection 46), or both.

Network Association and Security

In addition, as illustrated in FIG. 8, the master node device 42includes network association/security circuitry 76 for facilitatingassociation of the welding equipment/accessory node devices 52 with themaster node device 42, as well as ensuring that weldingequipment/accessory node devices 52, the master node device 42, and theassociated welding power supply unit 12 operate securely with each otherby, for example, preventing unauthorized access to the local wirelessnetwork 40 formed between the welding equipment/accessory node devices52 and the master node device 42.

As described above, the communications traffic from each weldingequipment/accessory node device 52 is sent to the master node device 42,which acts as a router and prioritization controller, and whichultimately routes the correct messages to the final destination as shownin FIGS. 4 and 5. The local wireless network 40 that is formed betweenthe welding equipment/accessory node devices 52 and the master nodedevice 42 will be secure insofar as only welding equipment/accessorynode devices 52 having proper credentials (e.g., indicating that thedevice is an authorized and certified device appropriate for use withthe master node device 42) and having been synchronized based on “userintent” input (e.g., via depression of synchronization mechanisms, suchas the association buttons 70 described above) are allowed to“associate” with the local wireless network 40. Furthermore, the masternode device 42 is only allowed to control one welding power supply unit12, thereby further enhancing the security of the formed local wirelessnetwork 40.

As described above, in certain embodiments, the association procedurecarried out by the network association/security circuitry 76 isinitiated by manually pressing and holding a specially designedassociation button 70 of each device involved in the pairing step, suchthat the pairing is always performed between the master node device 42and each device the operator wishes to add to the local wireless network40. Once a welding equipment/accessory node device 52 has beensuccessfully registered and associated with the master node device 42,it will remain as an active participant in the local wireless network 40until the local wireless network 40 is dissolved. Following dissolutionof the local wireless network 40, each welding equipment/accessory nodedevice 52 and the master node device 42 are free to become associatedwith other local wireless networks 40.

The master node device 42 (e.g., using the network association/securitycircuitry 76) will determine through preliminary communication with thewelding equipment/accessory node device 52 that it is the master nodedevice 42 in the communication session, and that the other node in thecommunication session is a welding equipment/accessory node device 52with the proper authorization credentials, MAC address, and securityaccess code, among other things. This verification is necessary in orderto prevent other wireless devices (e.g., Zigbee wireless devices) thatare not authorized and certified, and which do not meet the safety andreliability standards, from joining the local wireless network 40 andbeing able to exchange data with other devices on the local wirelessnetwork 40.

Once a welding power supply unit 12 is accepted by the master nodedevice 42, the two initial devices form the local wireless network 40.The first device to join the master node device 42 in the process offorming the local wireless network 40 is always the welding power supplyunit 12, or dongle-type device 64, thus the simplest and smallestnetwork consists of at least one controller, normally identified as themaster node device 42, and an accessory node such as the welding powersupply unit 12, which is considered the device expected to be controlledby the network controller (i.e., the master node device 42).

Soon after establishing the local wireless network 40, the networkassociation/security circuitry 76 of the master node device 42 (again,commonly referred to as the network controller) will program theaccessory node with a channel number, a sleep/wakeup timer value, aninitial transmission power level, and other parameters needed to controltransmissions within the local wireless network 40. The networkassociation/security circuitry 76 of the master node device 42 will alsoinquire status information from the accessory node, such as batterylevel, receiver sensitivity, and other parameters which are helpful inmanaging the RF resources of the accessory node. It will be appreciatedthat these steps will also be done with the various weldingequipment/accessory node devices 52 that are subsequently added to thelocal wireless network 40 (e.g., not just the welding power supply unit12 or dongle-type device 64 upon initiation of the local wirelessnetwork 40).

The association method described herein is different from typicalassociation methods (e.g., Zigbee association methods) which allowwireless nodes to connect simply by providing a unique serial number(e.g., Node ID). When implementing a control and communication network,such methods do not provide a desired level of security since virtuallyany device can mimic a Node ID in the correct manufacturer range andproper format, and can therefore be granted access in situations whereaccess is not appropriate, which can result in unsafe operation, amongother things.

As briefly described above with respect to FIG. 7, when the networkassociation/security circuitry 76 of the master node device 42 noticesassociation key presses from the user (e.g., depression of thededication association buttons 70) on two devices, the networkassociation/security circuitry 76 initiates the association process. Thenetwork association/security circuitry 76 remains in the associationmode for as long as the buttons 70 remain pressed by the user. While inassociation mode, the network association/security circuitry 76initially sets the communication channel to 15, requests a clear channelassessment on Channel 15, and lowers the transmission power of themaster node device 42 (e.g., of the wireless communication circuitry 72)to the lowest level allowed by the chipset (e.g., approximately −17 dBmin certain embodiments) in order to limit the transmission range fromwhich other welding equipment/accessory node devices 52 may hear itsbeacon and decide to join.

The master node device 42 then sends out a beacon on Channel 15,announcing its availability as a network coordinator for weldingequipment/accessory node devices 52 within the wireless transmissionrange. All association takes place on Channel 15 unless energy detectioncircuitry 78 of the master node device 42 and/or a weldingequipment/accessory node device 52 deems it a relatively noisy channel,at which point the next available channels (e.g., Channels 20, 25, and26) are used. In certain embodiments, the master node device 42 repeatsthe beacon every 10 milliseconds, and waits 20 milliseconds for aresponse from any welding equipment/accessory node device 52 wishing toassociate with the master node device 42. If no answer is received onChannel 15 for a given time period (e.g., 1000 milliseconds in certainembodiments) and algorithms of the energy detection circuitry 78 reportrelatively low energy (i.e., the channel is clear enough to communicateover), the network association/security circuitry 76 assumes that thereare no welding equipment/accessory node devices 52 wishing to associatewith the master node device 42, and terminates the associationtransaction. If the algorithms of the energy detection circuitry 78detect noise on Channel 15, and the user is still pressing theassociation button 70 on the master node device 42, the master nodedevice 42 will send out beacons on the next available channel (e.g.,Channel 20), repeating the beaconing procedure until either of twothings occurs: (1) a welding equipment/accessory node device 52 is foundand the association procedure is initiated by the networkassociation/security circuitry 76, or (2) a channel seek counter wrapsaround to a value of 15 after having traversed all other availablechannels (e.g., Channels 20, 25, and 26 in certain embodiments). As longas the user keeps pressing the association button 70 on the master nodedevice 42, the algorithms will keep switching through channels whennoise is present in order to find a clear channel that it can use tocomplete the association of a welding equipment/accessory node device 52to the master node device 42.

If a welding equipment/accessory node device 52 is detected, the masternode device 42 will request a MAC (media access control) address and anaccessory node function code, among other things, from the weldingequipment/accessory node device 52 in order to make a decision whetherto map the welding equipment/accessory node device 52 into the localwireless network 40 or to reject it. The method is different fromtypical node association methodologies (e.g., Zigbee) that allow devicesto associate if they are of the “correct” type (i.e., an End Point nodecan always connect to a Coordinator node). A welding equipment/accessorynode device 52 requesting association with the master node device 42must meet at least three minimum criteria. First, the weldingequipment/accessory node device 52 must have a “short network address”of 0xFFFF, which means that the welding equipment/accessory node device52 has not been persistently programmed with an address by anothermaster node device 42 (i.e., that it belongs to another local wirelessnetwork 40). Second, the welding equipment/accessory node device 52 mustpossess a MAC address in the proper manufacturer's range. Third, thewelding equipment/accessory node device 52 must possess the correctfunctionality per the sequence of association rules. For example, asdescribed above, the first node to connect to the master node device 42is the equipment node (e.g., the welding power supply unit 12 or otherindustrial equipment being controlled). In addition, duplication ofwelding equipment/accessory node device 52 types is limited and, in someinstances, prevented. For example, some node types are allowed to havemultiple instances of each type in the local wireless network 40, whilesome are not (e.g., there may be only one welding torch 18 per eachlocal wireless network 40, while there may be multiple sensors 66 pereach local wireless network 40). Furthermore, the association rulesensure that the minimum set of power save and data throughput arerequired by the type of local wireless network 40 the master node device42 will build.

Assuming the welding equipment/accessory node device 52 passes theminimum criteria for being associated with the master node device 42,the network association/security circuitry 76 will map the weldingequipment/accessory node device 52 into the local wireless network 40and program the welding equipment/accessory node device 52 with a “shortnetwork address” representing its functionality (within the localwireless network 40) and other hierarchical network parameters, as wellas sleep mode timing if the welding equipment/accessory node device 52is a battery powered device that needs to be temporarily put to sleepduring operation. Once the welding equipment/accessory node device 52has been added to the local wireless network 40, the networkassociation/security circuitry 76 will program the weldingequipment/accessory node device 52 with a heartbeat interval, and willexpect it to provide a periodic indication that it is still alive inorder to maintain the safety and security features of the local wirelessnetwork 40. The heartbeat data packet from the weldingequipment/accessory node device 52 may include the following data: (1)the battery level (e.g., high, medium, or low) of the weldingequipment/accessory node device 52, (2) the transmission power levelsetting of the welding equipment/accessory node device 52, (3) thereceiver sensitivity measured from the previous packet, and (4) optionalcustom signature of the welding equipment/accessory node device 52,among other things. It will be appreciated that, in certain embodiments,any and all subsets of this data may be provided by the weldingequipment/accessory node device 52.

If a welding equipment/accessory node device 52 drops off the localwireless network 40 due to an electrical or mechanical malfunction, andsuch welding equipment/accessory node device 52 fails to log threeconsecutive heartbeat cycles with the master node device 42, the networkassociation/security circuitry 76 will act in the following manner. Ifthe welding equipment/accessory node device 52 is actively controllingequipment such as the welding power supply unit 12 (e.g., it isdetermined that the last control command for the controlled equipmentcame from the welding equipment/accessory node device 52), then thenetwork association/security circuitry 76 will immediately disassociatethat welding equipment/accessory node device 52 from the local wirelessnetwork 40 and send an error flag to the welding equipment/accessorynode device 52 used to provide the user feedback. If the weldingequipment/accessory node device 52 is “safety non-critical” such as auser display device, then the network association/security circuitry 76will log the loss of the welding equipment/accessory node device 52 in abuffer, and will attempt to locate the welding equipment/accessory nodedevice 52 by repeating association beacons and only allow thatparticular welding equipment/accessory node device 52 with thatparticular address to automatically re-associate provided that: (1) thelocal wireless network 40 that associated the weldingequipment/accessory node device 52 in the first place is still running(e.g., the local wireless network 40 has not been dismantled), and (2)the short network address, node function, and manufacturer codes matchthe node that was detected to have been lost.

If any welding equipment/accessory node device 52 determines that it hasbecome disconnected from the local wireless network 40 with which it wasproperly associated, the welding equipment/accessory node device 52 willtake a series of intelligent steps to locate the master node device 42.For example, the welding equipment/accessory node device 52 may checkfor channel noise and switch channels away from a predefined channel(e.g., set by the master node device 42) that happens to be noisy. Inaddition, the welding equipment/accessory node device 52 may increaseits transmission power to the maximum allowable. Furthermore, thewelding equipment/accessory node device 52 may send out “distress”packets to the master node device 42 to tell it that the weldingequipment/accessory node device 52 has trouble with RF transmissions,for example. In response, as described in greater detail below, thenetwork association/security circuitry 76 of the master node device 42may adjust the “network footprint” (e.g., increase the signal strengthof the wireless communication circuitry 72 of the master node device 42)in order to mitigate the special circumstances of the “distressed node.”

If these steps fail, the welding equipment/accessory node device 52 willdetermine that it has been orphaned from the local wireless network 40it was associated with, and will reset itself into an un-associated typenode by, for example, changing its short network address to 0xFFFF,changing its communication channel to Channel 15, changing its status to“unassociated,” clearing its log and heartbeat settings, and puttingitself into a low power mode or OFF mode, waiting to be awakened by anoperator pressing its association button 70. The mechanism used by thewelding equipment/accessory node device 52 to tell if it is stillconnected to the master node device 42 is to observe the details of theacknowledge (“ACK”) packets sent by the master node device 42 inresponse to each of its heartbeat packets. Each packet, whetherheartbeat or not, will have to be acknowledged within a given timeperiod (e.g., 100 milliseconds in certain embodiments) by the masternode device 42. Other data collected as a result of reading the ACKpacket will help the welding equipment/accessory node device 52determine if it is in danger of losing the wireless communication linkwith the master node device 42. The mechanism for accomplishing this isdescribed in greater detail below.

If the network association/security circuitry 76 of the master nodedevice 42 decides to disband the local wireless network 40 it has formedas a result of losing the long-range communication connection 46 to thedevice being controlled (e.g., the welding power supply unit 12), itwill send each welding equipment/accessory node device 52 associatedwith the local wireless network 40 a request to disassociate, and willdelete its table entries of the device information that has respondedwith an ACK to its request to disassociate command. Once all weldingequipment/accessory node devices 52 previously associated with themaster node device 42 have been successfully disassociated, the masternode device 42 will enter a sleep mode or OFF mode and wait to beawakened by the user pressing its association button 70.

Improved Robustness

The wireless network architecture described herein allows for anindustrial wireless network architecture that is tolerant oftransmission interruptions, lost communication links, and data errorsnormally encountered in relatively noisy factory environments, andincludes methods of working around the physical limitations of RFtransmissions through protocol intelligence built into the nodes (e.g.,the master node devices 42 and the welding equipment/accessory nodedevices 52) making up the local wireless networks 40. The techniquesdescribed herein address the inherent nature of RF transmissions beingsomewhat unreliable. Any particular transmission may be lost or its datacorrupted and any link, no matter how solid it may have appeared at onetime, could quickly become an unreliable link. The intelligence fordealing with such physical limitations and providing improved networkrobustness are described in greater detail below. These techniquesensure continuous improvement (e.g., updated approximately every 100milliseconds in certain embodiments) of the reliability of the wirelesscommunication between the master node device 42 and the weldingequipment/accessory node devices 52 (as well as between the master nodedevice 42 and the associated welding power supply unit 12 in embodimentsusing a long-range wireless communication connection 46).

As described above, the communication links between the nodes (e.g., themaster node devices 42 and welding equipment/accessory node devices 52)making up the local wireless network 40 are established only when ahuman operator expresses intent to form the communication links by, forexample, pressing association buttons 70 on each device to be paired. Asalso described above, the network configuration of each local wirelessnetwork 40 is always a “star” configuration formed with the master nodedevice 42 acting as the master network controller between the weldingequipment/accessory node devices 52 and the CID (e.g., the welding powersupply unit 12). This guarantees only one master controller (i.e., themaster node device 42) is responsible for setting up and managing thelocal wireless network 40, allowing only the welding equipment/accessorynode devices 52 with appropriate credentials to join the local wirelessnetwork 40, and being aware of every source and destination of data inthe local wireless network 40.

In certain embodiments, when forming a link using the associationprocedures described above, the wireless communication circuitry 72 ofthe two nodes to be connected are set into the lowest RF power mode(e.g., having a relatively short transmission range) such that theirsignals cannot be detected by other more distant master node devices 42,such that there will be no mistake associating the nodes that theoperator intended to associate. For example, when the associationbuttons 70 on the nodes (e.g., the master node device 42 and a weldingequipment/accessory node device 52) to be associated are pressed, themaximum transmission range of the nodes may be adjusted to be less thanapproximately 2 feet.

As described above, the welding equipment/accessory node devices 52provide credentials to the network association/security circuitry 76 ofthe master node device 42, thereby proving they belong to the localwireless architecture described herein. For example, the weldingequipment/accessory node devices 52 provide an appropriate MAC addressrange, network device classification, network functionality, and correctassociated password, among other things. The credential requirements aredifferent than typical ad-hoc wireless connections normally allowedthrough Zigbee (802.15.4), WiFi (802.11.a/b/g/n), or Bluetooth(802.15.1), which typically allow any device with the proper radio tojoin a network provided the device specifies (in most cases) its networkfunctionality. The increased credential requirements described hereinguarantee that only devices manufactured and certified at the higheststandards are allowed to be part of the local wireless networks 40. Morespecifically, the increased credential requirements described hereinensure that all devices used in the local wireless networks 40 have beenfully tested and certified to operate relatively error-free. As such,conventional wireless devices (e.g., conventional Zigbee devices) willnot have access to the local wireless networks 40 set up by theoperators.

Once associated, a set of welding equipment/accessory node devices 52(through the respective master node device 42) can control one and onlyone welding power supply unit 12, removing the possibility ofinadvertently controlling other welding power supply units 12 in thevicinity. The stringent association rules guarantee the safety of humanoperators in an industrial setting. In addition, all communicationbetween nodes are encrypted with an AES (Advanced Encryption Standard)key published to the local wireless network 40 by each master nodedevice 42 at the time of formation of the local wireless network 40.Thus, communications between the nodes of the local wireless network 40cannot be hacked by a device in close RF proximity of the local wirelessnetwork 40.

Each welding equipment/accessory node device 52 in a local wirelessnetwork 40 has a hard-coded functionality classification that cannot bechanged except through a hardware modification of the code identifyingthe welding equipment/accessory node device 52. Thus, for example, awelding wire feeder 14 will always act as a wire feeder in any localwireless network 40 with which it is associated. In addition, thenetwork association/security circuitry 76 of each master node device 42will only allow a certain number of nodes of each specific functionalitytype that would be necessary to perform a particular welding task. Forexample, in certain embodiments, the master node device 42 may not allowmore than one welding wire feeder 14 or more than one welding torch 18to be associated with the local wireless network 40 since there is onlyone operator, only one welding torch 18 may be operated by the operatorat a time, and a given welding torch 18 only makes use of one weldingwire feeder 14 at a time. Conversely, multiple display nodes may beallowed since multiple devices can display data related to the weldingoperations. However, only one such display node (e.g., a given weldingpendant 36) is allowed to directly command the associated welding powersupply unit 12. In certain embodiments, control responsibility may bemoved from one device to another by the master node device 42 (providedthat the device includes the capability to control the welding powersupply unit 12), but may only reside in one particular device at any onetime.

The local wireless network 40 established through the association rulesdescribed above only exists for as long as the associated welding powersupply unit 12 is active. Once the welding power supply unit 12 has beenturned off or the dongle-type device 64 has been removed from the 14-pinconnector of the welding power supply unit 12, the local wirelessnetwork 40 is disbanded by the intelligent master node device 42. Inaddition, the master node devices 42 actively monitor the RF environmentaround themselves, and negotiate different channels with other masternode devices 42 in order to allow the maximum co-existence of localwireless networks 40 in relatively noisy industrial environments. Themaster node devices 42 also maintain the communication links between thewelding equipment/accessory node devices 52 and the welding power supplyunit 12 through detailed transmission acknowledgement, monitoring ofbattery lives, and RF quality and issuance of periodic heartbeats, forexample. All communication links in the local wireless network 40 areintelligently maintained for the duration of the life of the localwireless network 40.

If battery levels of welding equipment/accessory node devices 52 thatare not line-powered are deemed too low to provide acceptable RF links,the welding equipment/accessory node devices 52 are not allowed to jointhe local wireless network 40. In such an event, a status warning isshown to the operator of one of the display nodes in the local wirelessnetwork 40, such as the welding helmet 34 or the welding pendant 36,requesting that the operator charge the battery of the weldingequipment/accessory node device 52 with the low battery capacity. Inaddition, as described in greater detail below, the master node device42 constantly monitors power levels in each of the weldingequipment/accessory node devices 52 of the local wireless network 40 toensure that the welding equipment/accessory node devices 52 will be ableto wake up (if they are battery powered) at a programmed wake time, andbe able to maintain their respective wireless communication link withthe master node device 42.

Once associated with the local wireless network 40, each weldingequipment/accessory node device 52 will provide heartbeat packets to themaster node device 42 at pre-determined time intervals. Missing acertain number of heartbeats in a row is usually indicative of the RFlink between the particular welding equipment/accessory node device 52and the master node device 42 having been lost, and the weldingequipment/accessory node device 52 will be disassociated from the localwireless network 40.

In addition, the energy detection circuitry 78 of the master node device42 continuously monitors channel noise on the current channel to makesure there is an expectation of acceptable “quality of service” in orderfor transmissions to occur within the local wireless network 40. Ifnoise detected on the current channel is above a certain (e.g.,predetermined or pre-set) threshold, the master node device 42 will finda relatively clear channel and move all of the weldingequipment/accessory node devices 52 in its local wireless network 40 tothe new channel. The master node device 42 also continuously monitorsreceiver sensitivity data provided by each welding equipment/accessorynode device 52, and adjusts it transmission power (e.g., the signalstrength of the wireless communication circuitry 72) accordingly inorder to ensure that the master node device 42 sends data out atappropriate signal strengths to be reliably detected by all of thewelding equipment/accessory node devices 52 in its local wirelessnetwork 40, but to not be “too loud” to disturb other networks nearby.In other words, the master node device 42 utilizes the receiversensitivity data from the welding equipment/accessory node devices 52 assignal strength feedback data to appropriately adjust the signalstrength of transmission from the master node device 42. In addition,the master node device 42 may cause the transmission power of thewelding equipment/accessory node devices 52 to be similarly adjusted.

Loss of the long-range communication connection 46 between the masternode device 42 and the welding power supply unit 12 will be detectedquickly by the welding power supply unit 12, and the device will beplaced in a safe mode of operation. Certain methods for mitigating thetemporary loss of RF links, as well as methods to re-establish a lostlink, are described in greater detail above. These methods ensure thatthe maximum effort is made by the master node devices 42 and the weldingequipment/accessory node devices 52 in order to maintain what mightotherwise be viewed as unreliable RF links.

In addition, the data transferred to and from the master node device 42and the welding equipment/accessory node devices 52 will be packetizedin optimum size packets. As described above, the star topology of thelocal wireless networks 40 guarantees a single intelligent controller(e.g., the master node device 42) for each local wireless network 40,along with orderly transmissions of data between the master node device42 and the welding equipment/accessory node devices 52. This ensuresthat the minimum amount of wireless transmissions take place and thewelding equipment/accessory node devices 52 do not spend their timearbitrating for their turn to communicate, as in conventional ad-hoctopologies. The master node device 42 receives data from all of thewelding equipment/accessory node devices 52 in its local wirelessnetwork 40, and the master node device 42 packetizes and sends the datato the final destination using the optimum packet size and timing, whichis determined in real time (e.g., updated approximately every 50milliseconds in certain embodiments) from historical performancemonitoring of the local wireless network 40. This helps reducecollisions of data transmissions between different weldingequipment/accessory node devices 52 while improving transmissionquality.

Power Management and Optimization

Some (or all) of the welding equipment/accessory node devices 52 will bepowered by on-board batteries 80, as opposed to being plugged intosources of power, to facilitate the portability of the weldingequipment/accessory node devices 52 among remote locations. In order tofacilitate the use of on-board batteries 80 in all weldingequipment/accessory node devices 52 in the local wireless network 40 (aswell as the master node devices 42 and the welding power supply unit12), the master node devices 42 (as well as the other devices) includepower optimization circuitry 82 configured to use unique methods to savepower among the welding equipment/accessory node devices 52 while stillmaintaining the necessary minimum latency and adequate levels ofavailability. These power optimization methods implement adaptivealgorithms to determine what the optimum sleep/awake timing is for eachlocal wireless network 40 independent of other wireless networks whilestill mainlining the required level of availability.

Following the pairing procedures described above, the power optimizationcircuitry 82 of the master node device 42 determines at least thefollowing parameters about the local wireless network 40 it hasassembled: (1) the number of welding equipment/accessory node devices 52in the local wireless network 40, (2) the types of weldingequipment/accessory node devices 52 in the local wireless network 40,(3) the timing requirements (e.g., maximum latency) of the most criticalwelding equipment/accessory node devices 52, (4) the transmission powerfootprint of the local wireless network 40 from the last set oftransmissions associated with each welding equipment/accessory nodedevice 52, and (5) the optimum channel to operate in (e.g., the leastamount of measured noise from nearby devices, as described above). Usingthis information, as described in greater detail below, the poweroptimization circuitry 82 of the master node device 42 formulates a“sleep mode strategy” and schedule for all the weldingequipment/accessory node devices 52 under its control to ensure that allparameters of the local wireless network 40 are met.

The power optimization circuitry 82 of the master node device 42 beginsby setting the network latency of the local wireless network to that ofthe most stringent requirement of any of the welding equipment/accessorynode devices 52 in the local wireless network 40. For example, the localwireless network 40 will be set to respond at least within 100milliseconds if the requirements of the welding wire feeder 14 are thatits feed rate must be updated no less frequently than every 100milliseconds. The node controlling the Controlled Industrial Device(CID) (e.g., the welding power supply unit 12) has been referred toherein as, for example, the dongle-type device 64. This device node isassumed to always be powered by an AC power source, such as the powersource 30 illustrated in FIG. 1, so that it is always available to sendalerts to the master node device 42 or to receive commands from themaster node device 42. This device node has a maximum latencyrequirement determined by safety requirements as well as certain loopdynamics of its control systems.

The power optimization circuitry 82 of the master node device 42determines a “practical latency” time for each weldingequipment/accessory node device 52 in the local wireless network 40 suchthat the welding equipment/accessory node devices 52 that are notcritical to the safe operation of the equipment can spend more time insleep mode since, for example, user updates are not as critical. Ingeneral, the welding power supply unit 12, the welding wire feeder 14,and the welding control pendant 36 are considered to be critical to thesafe operation of the equipment. Each welding equipment/accessory nodedevice 52 that can support a practical latency parameter (e.g., lessstringent latency requirement) will communicate this fact to the masternode device 42 upon completion of the pairing and association proceduredescribed above. In general, the practical network latency parametersare acceptable response times that are generally greater than theoverall network latency parameter of the local wireless network 40 thatis set based on the most stringent requirements of the local wirelessnetwork, as described above.

The power optimization circuitry 82 of the master node device 42programs each welding equipment/accessory node device 52 with a nextwake up time minus a “network latency parameter,” which is initiallydetermined from full-time operation (e.g., during the first five minutesfollowing formation of the local wireless network 40), and communicatesto the welding equipment/accessory node devices 52 to place themselvesin sleep mode as soon as their individual tasks list is empty (e.g.,there are no pending requests or schedules tasks due). In certainembodiments, this network latency parameter is calculated to be twicethe average transmission latency for the slowest weldingequipment/accessory node device 52 in the local wireless network 40. Incertain embodiments, adjustments to the network latency parameter aremade if the average latency of the last three transmissions is higherthan the initially calculated value, which means that over time thewelding equipment/accessory node devices 52 require more time to wake upand communicate with the master node device 42 due to possible increasesin noise on a certain channel, overcrowding of the RF spectrum bymultiple noise sources, and so forth. In addition, the poweroptimization circuitry 82 of the master node device 42 places the masternode device 42 into sleep mode for a duration of time that isapproximately 95% of the amount of time that it programmed all of thewelding equipment/accessory node devices 52 in the local wirelessnetwork 40. When the master node device 42 is placed in sleep mode, allnetwork-specific information (e.g., routing tables, latency timing, nodefunctionality, and so forth) are stored into non-volatile random accessmemory (RAM) 84 of the master node device 42 for use when the masternode device 42 wakes up.

While in sleep mode, the master node device 42 monitors special operatorinput devices 86 on the master node device 42 (e.g., touch screens,buttons, keys, switches, and so forth, on an exterior surface of themaster node device 42, as illustrated in FIG. 7) in the event that theoperator needs to communicate with the CID (e.g., the welding powersupply unit 12) sooner than the network latency would otherwise permit.Activating any of these operator input devices 86 produces aninterruption to a processor 88 (e.g., a microprocessor, in certainembodiments) controlling the master node device 42, which wakes themaster node device 42 from sleep mode, allowing the master node device42 to start communicating with the welding equipment/accessory nodedevices 52 in the local wireless network 40. For example, an operatormay pick up a welding control pendant 36 (functioning as the master nodedevice 42 for the local wireless network 40) that is in sleep mode, andpress a button on the welding control pendant 36, which serves as thewake event for the processor 88. The processor 88 wakes up due to theinterrupt caused by the button press, interprets the button press as aspecific command, sends that command to the CID (which never goes intosleep mode), and shortly thereafter acknowledges and executes therequested command. If a node other than the CID or master node device 42(e.g., the welding equipment/accessory node devices 52) receives a userinput in a similar manner, its own processor 88 (e.g., a microprocessor,in certain embodiments) will log the command in a queue in its ownnon-volatile random access memory (RAM) 84, and wait for the networklatency timer to expire before sending the information to the masternode device 42.

The embodiments described herein also allow for the CID (e.g., thewelding power supply unit 12) and/or dongle-type device 64 to be poweredby on-board batteries 80 (e.g., in a case of an engine drive unit whenthe main motor has been shut off). In this case, the CID or dongle-typedevice 64 will observe the standard sleep mode operation of the weldingequipment/accessory node devices 52 and the master node device 42, asdescribed above. The minimum latency value the CID or dongle-type device64 will report to the master node device 42 will take into account allof the timing dynamics and requirements of the CID or dongle-type device64 to make sure that it is safe for it to respond within the allocatednetwork latency. The local wireless network 40 established according tothe association procedures described above will persist through aninfinite number of sleep states for as long as the local wirelessnetwork 40 is not purposely disbanded.

The battery monitoring methodology described herein allows for timelyand accurate user notifications to ensure that the capacities of theon-board batteries 80 of the welding equipment/accessory node devices 52are managed and that such information is properly displayed to the user.For example, each welding equipment/accessory node device 52 sendsbattery status information to the master node device 42, which willprovide a display 90 (see, e.g., FIG. 7) to the user of each node'sremaining battery capacity. In certain embodiments, such notificationwill show a graphical representation of the battery level with a 5% orbetter resolution of the remaining battery capacity, along with a“Remaining Usage Time” display (e.g., in hours and minutes) undercurrent usage conditions. In addition, in certain embodiments, themaster node device 42 may display the same information relating to itsown battery capacity and remaining usage time. Charging information mayalso be transmitted to the master node device 42 from each weldingequipment/accessory node device 52 and displayed on the display 90 whensuch node is plugged into a battery charger. For example, the charginginformation may show the “Charge Current” as well as an estimated timeto full charge. Furthermore, in certain embodiments, the master nodedevice 42 may provide for visual and/or audible alarms in the event thatbattery levels of any of the welding equipment/accessory node devices 52fall below a given threshold (e.g., below approximately 30%) and willcontinue to provide periodic alarms until the particular on-boardbattery 80 is recharged. In addition, in certain embodiments, the masternode device 42 will disassociate a welding equipment/accessory nodedevice 52 if its on-board battery 80 runs out of power, and will reportto the user the action taken through audio and/or visual cues via thedisplay 90.

Sensor Data Transmission

As described above, sensors 66 that may not necessarily be involved withthe welding operations may also utilize the local wireless networks 40set up by factory personnel. As the local wireless networks 40 areestablished randomly and may only exist for a relatively short period oftime, the sensors 66 may continually have to try and find a master nodedevice 42 that it can associate with and be able to transfer its datapayload to an external destination (e.g., to cloud storage or othercentralized and/or distributed control system). In certain embodiments,a sensor 66 will take samples of its designated monitoring input(s) atregular intervals (e.g., approximately every 100 milliseconds), whichmay be programmable through the wireless links, and buffer the data inits non-volatile memory until the sensor 66 is able to connect to alocal wireless network 40 and send the buffered data to its finaldestination. In certain embodiments, the sensors 66 may initially beprogrammed with a hard-coded destination IP address, which representsthe target location to which the sensor 66 should send its data. Thedestination IP address may then be changed (e.g., through a master nodedevice 42 or other display device of a local wireless network 40) by arequestor with appropriate credentials.

The sensors 66 may associate with available master node devices 42 asfollows. An unassociated sensor 66 may wake up and listen for beaconssent out by any master node device 42 nearby that is announcing thatthey are the master node device 42 of a currently established localwireless network 40, and that they are ready to allow association withany nearby sensors 66 (or welding equipment/accessory node devices 52).If a master node device 42 is detected within RF range of the sensor 66,the sensor will request permission to associate with the master nodedevice 42. At this point, the master node device 42 and the sensor 66will exchange credentials in the same manner as the master node deviceand the welding equipment/accessory node devices 52 exchangecredentials, as described in greater detail above. For example, thesensor 66 will convey information to the master node device relating toan appropriate MAC address range, network device classification, networkfunctionality, and correct associated password, among other things, andthe network association/security circuitry 76 of the master node device42 will determine if the sensor 66 is compatible with the master nodedevice 42. If the sensor 66 and the master node device 42 are determinedto be compatible, a data link connection between the sensor 66 and themaster node device 42 is established. This connection is not the same asthe typical “command and control” associations made with the weldingequipment/accessory node devices 52. Rather, the connection between thesensor 66 and the master node device 42 merely allows sensor data tomove between the sensor 66 and some other destination end point. Inother words, the master node device 42 functions as an intelligentrouter for the sensor data to/from the sensor 66.

Once a connection link is established between the sensor 66 and themaster node device 42, the sensor 66 will request a “capabilities list”from the master node device 42. This capabilities list tells the sensor66: (1) if the master node device 42 has access to the World Wide Web(WWW), (2) if the master node device 42 is aware of other master nodedevices 42 in the vicinity with access to the WWW, (3) the lifetimeduration of the local wireless network 40 established by the master nodedevice 42, (4) the battery status of the master node device 42 (andwhether it is line-powered or battery-powered), and (5) the sleep periodof the local wireless network 40 controlled by the master node device 42(with which the sensor 66 may synchronize itself). It will beappreciated that, in certain embodiments, the “capabilities list” mayinclude a subset of these listed items.

If the master node device 42 advertised a connection to the WWW, or ifthe master node device 42 to which the sensor 66 is associated withknows of other master node devices 42 in the nearby vicinity that haveadvertised connections to the WWW, the sensor 66 will send a pingrequest to the master node device 42 presenting the final destination ofits data repository. The master node device 42 may have an Internetconnection itself, in which case the master node device 42 acts as abridge between the local wireless network 40 that it masters and theWWW, or it may forward requests through the back end of the CID (e.g.,the welding power supply unit 12), as described above.

If the master node device 42 does not advertise a connection to the WWW,or any knowledge of how to access the WWW (e.g., through other masternode devices 42), the sensor 66 will disassociate itself from the masternode device 42 to which it was briefly connected for the purpose ofassessing access of the master node device 42 to the WWW, and willcontinue its discovery routine, as described above. In certainembodiments, if a previously detected master node device 42 is againdetected by the discovery routine of the sensor 66, the master nodedevice 42 will store the hard-coded MAC address of the sensor 66 in itsmemory 84 as having been one that was connected briefly (e.g., for thepurpose of WWW access capability assessment) and will disallowassociation to its local wireless network 40 unless the master nodedevice 42 has gained access to the WWW in the time since the lastassociation with the sensor 66 was requested. As such, time will besaved for the sensor 66 so that the sensor 66 does not unnecessarilywaste battery power reassessing what was already determined (i.e., thatthe master node device 42 cannot provide access to the WWW).

If the master node device 42 can provide access to the WWW to the sensor66, the master node device 42 will attempt to send a ping to thedestination address provided by the sensor 66, and will wait for aresponse from the destination address. If the master node device 42receives a ping response from the destination address, and thedestination address is valid, the master node device 42 will inform thesensor 66 that a communication link with the destination address can beestablished, and that it is ready to receive data from the sensor 66.The sensor 66 will then send a count of total packets it intends totransfer to the destination address, along with the first packet ofdata. The master node device 42 will buffer the data, perform all thesecurity and checksums on the data to make sure it has not beencorrupted, and send the data packet to the destination address that itpinged earlier for the sensor 66.

The server at the final destination will accept the data, calculate achecksum, and send the checksum and a “current received packet” count asan ACK to the master node device 42. The master node device 42 willforward the ACK information received from the server at the finaldestination to the sensor 66. If satisfied with the ACK information, thesensor 66 will decrement its packet count and send the next packet tothe master node device 42. The sensor 66 will permanently delete alldata from its non-volatile memory buffer that has been acknowledged tohave been successfully received by the server at the final destinationIP address. In addition, the sensor 66 will make a log entry in a“circular buffer log” showing the time and date, size of datatransferred to the final destination, as well as the time and date rangeof the data that was transferred. In the event that the sensor 66 hasbeen unable to access the WWW through any nearby master node devices 42(e.g., with the proper access capabilities) for a long time, and thesensor 66 is running out of non-volatile buffer memory, the sensor 66will start deleting the oldest sensor data to make room for the newestsensor data collected.

The data collection methods and timing parameters, sleep/wake up andsearch timing parameters, and final destination IP address parameters ofthe sensors 66 are all reprogrammable wirelessly from a server withproper credentials and whose origination (source) IP address match thefinal destination IP address of the particular sensor 66. Thus, only theserver being sought by the sensor 66 as its final destination, and whichhas received and acknowledged at least one packet of data from thesensor 66, has the right to change the IP address settings and othersettings of the sensor 66 following a successful exchange ofcredentials. The server at the final destination with the propercredentials also has the ability to inquire about the current settingsof the sensor 66 and transmit logs to be sent to it on demand. Suchstatus information requested by the final destination server will not bedeleted on the sensor 66 as standard sensor data is normally deletedfollowing successful upload to the server.

The mesh type connection of master node devices 42 allows sensor data tofind a path to a welding cell that has access to the Internet. FIG. 9 isa schematic diagram illustrating the topology of a mesh-type network 92of a plurality of master node devices 42 and associated local wirelessnetworks 40 (e.g., weld cells) that communicate with each other andshare information about each other's capabilities, thereby facilitatingsensor data transmission from a plurality of sensors 66, in accordancewith embodiments of the present disclosure. While the master nodedevices 42 can only each control their own local wireless network 40 andassociated welding power supply unit 12, the master node devices 42 cancommunicate with each other and allow sensor data to move from masternode device 42 to master node device 42 until it reaches a device thathas access to the Internet. Such a device may be a welding power supplyunit 12 with a built-in gateway between the front end (industrialcontrol side) and back end (Internet access), such as weld cell #3illustrated in FIG. 9. A range extending wireless router 68 notassociated with any of the local wireless networks 40 can also act as agateway to the Internet if a higher level of service guarantee isdesired, since the formation of local wireless networks 40 may berelatively random in a typical factory setting.

Returning now to FIG. 8, certain elements of the master node device 42and the welding equipment/accessory node devices 52 (e.g., the networkassociation/security circuitry 76, the energy detection circuitry 78,and the power optimization circuitry 82) are characterized as being“circuitry.” It will be appreciated that, in certain embodiments, thiscircuitry may be embodied as hardware, a combination of hardware andsoftware, or only software. For example, in certain embodiments wherethis circuitry is software, the circuitry may include computer-readableinstructions that are stored in memory 84, and that are executable onthe processor 88 of the particular device. However, in otherembodiments, the circuitry may also include hardware elements. Forexample, in certain embodiments, the energy detection circuitry 78 mayinclude certain hardware elements that assist in detecting noise levels.

While only certain features of the invention have been illustrated anddescribed herein, many modifications and changes will occur to thoseskilled in the art. It is, therefore, to be understood that the appendedclaims are intended to cover all such modifications and changes as fallwithin the true spirit of the invention.

The invention claimed is:
 1. A system, comprising: a master node devicecomprising: communication circuitry configured to facilitatecommunication with internal communication circuitry of a welding powersupply unit via a long-range communication link, and to facilitatewireless communication with internal wireless communication circuitry ofone or more welding-related devices via a short-range wirelesscommunication network; and control circuitry configured to continuouslyimprove reliability of communications between the internal communicationcircuitry of the welding power supply unit and the internal wirelesscommunication circuitry of the one or more welding-related devices bycontinuously improving reliability of transmission of data between theinternal communication circuitry of the welding power supply unit andthe internal wireless communication circuitry of the one or morewelding-related devices by limiting a number of welding-related devicesassociated with the short-range wireless communication network based atleast in part on functionality types of the welding-related devices,wherein the functionality types of the welding-related devices includetypes of functionality relating to a welding task that thewelding-related devices are configured to perform.
 2. The system ofclaim 1, wherein the control circuitry continuously improves thereliability of the transmission of the data between the internalcommunication circuitry of the welding power supply unit and theinternal wireless communication circuitry of the one or morewelding-related devices by allowing association of the one or morewelding-related devices with the short-range wireless communicationnetwork only if the welding-related devices include authorizationcredentials that indicate the welding-related devices may be used withthe master node device.
 3. The system of claim 2, wherein theauthorization credentials include at least a media access control (MAC)address and a function code of the welding-related devices.
 4. Thesystem of claim 1, wherein the control circuitry continuously improvesthe reliability of the transmission of the data between the internalcommunication circuitry of the welding power supply unit and theinternal wireless communication circuitry of the one or morewelding-related devices by encrypting and decrypting the data.
 5. Thesystem of claim 1, wherein the control circuitry continuously improvesthe reliability of the transmission of the data between the internalcommunication circuitry of the welding power supply unit and theinternal wireless communication circuitry of the one or morewelding-related devices by continuously monitoring battery levels andstatuses of the one or more welding-related devices.
 6. The system ofclaim 1, wherein the control circuitry continuously improves thereliability of the transmission of the data between the internalcommunication circuitry of the welding power supply unit and theinternal wireless communication circuitry of the one or morewelding-related devices by switching to a new communication channel whennoise on a current communication channel exceeds a threshold.
 7. Thesystem of claim 1, wherein the control circuitry continuously improvesthe reliability of the transmission of the data between the internalcommunication circuitry of the welding power supply unit and theinternal wireless communication circuitry of the one or morewelding-related devices by actively adjusting signal strength of thecommunication circuitry based at least in part on signal strengthfeedback data from the one or more welding-related devices.
 8. Thesystem of claim 1, wherein the one or more welding-related devicescomprise a welding wire feeder.
 9. The system of claim 1, wherein theone or more welding-related devices comprise a welding torch.
 10. Thesystem of claim 1, wherein the one or more welding-related devicescomprise a welding helmet.
 11. The system of claim 1, wherein the one ormore welding-related devices comprise a welding pendant.
 12. The systemof claim 1, wherein the one or more welding-related devices comprise awelding foot pedal.
 13. The system of claim 1, wherein a welding-relateddevice of the one or more welding-related devices comprises the masternode device.
 14. The system of claim 1, wherein the communicationcircuitry includes radio frequency (RF) transmitters and sensors.
 15. Amethod, comprising: wirelessly communicating between internal wirelesscommunication circuitry of one or more welding-related devices and amaster node device via a short-range wireless communication network;communicating between the master node device and internal communicationcircuitry of a welding power supply unit via a long-range communicationlink; and continuously improving reliability of communications betweenthe internal wireless communication circuitry of the one or morewelding-related devices and the internal communication circuitry of thewelding power supply unit by continuously improving reliability oftransmission of data between the welding power supply unit and the oneor more welding-related devices by limiting a number of welding-relateddevices associated with the short-range wireless communication networkbased at least in part on functionality types of the welding-relateddevices, wherein the functionality types of the welding-related devicesinclude types of functionality relating to a welding task that thewelding-related devices are configured to perform.
 16. The method ofclaim 15, wherein continuously improving the reliability of theshort-range wireless communication network comprises allowingassociation of the one or more welding-related devices with theshort-range wireless communication network only if the welding-relateddevices include authorization credentials that indicate thewelding-related devices may be used with the master node device, whereinthe authorization credentials include at least a media access control(MAC) address and a function code of the welding-related devices. 17.The method of claim 15, wherein continuously improving the reliabilityof the short-range wireless communication network comprises encryptingand decrypting the data transmitted via the short-range wirelesscommunication network.
 18. The method of claim 15, wherein continuouslyimproving the reliability of the short-range wireless communicationnetwork comprises continuously monitoring battery levels and statuses ofthe one or more welding-related devices.
 19. The method of claim 15,wherein continuously improving the reliability of the short-rangewireless communication network comprises switching to a newcommunication channel when noise on a current communication channelexceeds a threshold.
 20. The method of claim 15, wherein continuouslyimproving the reliability of the short-range wireless communicationnetwork comprises actively adjusting signal strength of the master nodedevice based at least in part on signal strength feedback data from theone or more welding-related devices.
 21. The method of claim 15, whereinthe short-range wireless communication network comprises a wirelesscommunication network having a transmission range of approximately 20-25feet from the master node device, and wherein the long-rangecommunication link comprises a wireless communication link having atransmission range of approximately 300 feet or more from the masternode device to the welding power supply unit.
 22. The method of claim15, wherein the one or more welding-related devices comprise a weldingwire feeder, a welding torch, a welding helmet, a welding pendant, or awelding foot pedal.
 23. The method of claim 15, wherein awelding-related device of the one or more welding-related devicescomprises the master node device.
 24. A wireless communication network,comprising: one or more welding-related devices, wherein the one or morewelding-related devices comprise a welding wire feeder, a welding torch,a welding helmet, a welding pendant, or a welding foot pedal; a weldingpower supply unit configured to convert power from a power grid to powerfor a welding operation performed using the one or more welding-relateddevices; and a master node device configured to facilitate wirelesscommunication between internal wireless communication circuitry of theone or more welding-related devices and the master node device via ashort-range wireless communication network, to facilitate communicationbetween the master node device and internal communication circuitry ofthe welding power supply unit via a long-range communication link, andto continuously improve reliability of communications between theinternal wireless communication circuitry of the one or morewelding-related devices and the internal communication circuitry of thewelding power supply unit by continuously improving reliability oftransmission of data between the internal wireless communicationcircuitry of the one or more welding-related devices and the internalcommunication circuitry of the welding power supply unit by limiting anumber of welding-related devices associated with the short-rangewireless communication network based at least in part on functionalitytypes of the welding-related devices, wherein the functionality types ofthe welding-related devices include types of functionality relating to awelding task that the welding-related devices are configured to perform.